LAUSR

The scattered field from the seafloor is often measured using short, broadband pulses, whereas many models for the mean scattered intensity are in the frequency domain. This As higher resolution seafloor mapping systems, i.e., synthetic aperture sonar, become more common, it is important to understand the effects of high resolution on measurements of both the averaged scattered intensity, and the distribution of the envelope of the scattered field. To address this problem, Monte Carlo simulations of the scattered field due to rough interfaces separating two fluids are perform. The integral equation governing the total pressure, the Helmholtz-Kirchhoff integral equation, is numerically solved using the boundary element method. Simulations are performed both in the limit of pressure release, as well as for more realistic sediment sound speed and density parameters. The von-Karman spectrum is used to generate random rough surfaces. Fourier synthesis is used to to generate time domain signals, which are then analyized in terms of the mean energy and amplitude distribution. The dependence of the scattering cross section and scintillation index on signal bandwidth (resolution) is examined. It is found that there is no observable dependence of the scattering cross section on bandwidth, but that there is significant dependence of the scintillation index.The scattered field from the seafloor is often measured using short, broadband pulses, whereas many models for the mean scattered intensity are in the frequency domain. This As higher resolution seafloor mapping systems, i.e., synthetic aperture sonar, become more common, it is important to understand the effects of high resolution on measurements of both the averaged scattered intensity, and the distribution of the envelope of the scattered field. To address this problem, Monte Carlo simulations of the scattered field due to rough interfaces separating two fluids are perform. The integral equation governing the total pressure, the Helmholtz-Kirchhoff integral equation, is numerically solved using the boundary element method. Simulations are performed both in the limit of pressure release, as well as for more realistic sediment sound speed and density parameters. The von-Karman spectrum is used to generate random rough surfaces. Fourier synthesis is used to to generate time domain signals, which are then ...